Abstract
We studied oligomeric properties of betaretroviral Mason-Pfizer monkey virus (M-PMV) non-myristoylated matrix protein (MA) and its R55F mutant in solution by means of nuclear magnetic resonance (NMR) spectroscopy. Using concentration-dependent NMR chemical shift mapping we have proven that the wild type (WT) MA forms oligomers in solution.
Conversely, no oligomerization was observed for the R55F mutant. Structural comparison of matrix proteins explains their different behavior in solution, concluding that the key residues involved in the intermonomeric interaction residues are exposed in WT MA while being buried in the mutant, which prevents the oligomerization of R55F.
The final model of oligomerization of wt MA was derived by a novel method of concerted use of the chemical shifts mapping and diffusion-ordered spectroscopy (DOSY) measured on a set of protein samples with varying concentrations.